La Petite Gemme Prairie Earthcache EarthCache

La Petite Gemme Prairie was part of the largest grassland on earth.  The name is French for “the little gem” and recognizes the French influence on Missouri as well as the gemlike quality of this small but geologically valuable prairie. This prairie just south of Bolivar, Missouri, is part of what was once known as “three mound prairie” that ran south from Bolivar along what is today the Highway 13 corridor.

The Great Plains included an area running 800 miles east of the Rocky Mountains and 3,000 miles from Canada to Mexico.  Today less than one percent of North American native prairie remains. Long ago one third of Missouri was prairie, and La Petite Gemme Prairie has been preserved as a small example of this phenomenon. 

What is a prairie and how is it formed? Millions of years ago, during the Missourian period of the Carboniferous stratigraphy of North America, entire areas of the Great Plains (including Missouri) were covered by a vast shallow inland sea. As the sea filled and receded due to runoff from the newly uplifted Rocky Mountains, mineral-rich silt, clay, sand and decaying marine life fell to the bottom of the sea. These deposits later evolved into limestone, sandstone, shale and a layer of calcium-rich soil. This layer of soil, with a high pH, created the perfect conditions for various grasses to grow, resulting in prairies. Grasses such as Big and Little Bluestem covered the plains, and as they died additional organic material helped the soil. Prairie fires caused by lightning turned to ash that also enriched the soil for new growth.

La Petite Gemme Prairie rises from the parking area to a prominent hill underlain by limestone to the south. As you may not have thought, all prairies are not flat. As you walk the prairie you will need to make observations to complete the following three requirements necessary to log this earthcache. It is about a .25 mile hike from the parking area to the highest point on the prairie.

To log this cache successfully, please e-mail me the answers to these three questions:
 

   
1: Take an elevation reading in the parking lot and compare it to the elevation at coordinates N 37 33.671  W093 24.574.  What is the approximate difference in elevation between the two points?

2: Describe the texture and color of the top soil approximately 30 ft south of the parking area.

3: At coordinates N37 33.827   W093 24.588, what is different about the top soil surface from the area in item number 2 and what do you think caused this difference?

Please do not post the answers with your log, just email them to me.